Facebook (Nasdaq: FB) has opened its messenger application beyond the social network’s one billion-plus members.

The Menlo Park, California-based announced the shift a brief message Tuesday morning. The shift in Facebook’s stance towards its Messenger app is the first time the young company has made an app available to users without an active Facebook account.

“Starting today, you can create a Messenger account with just your name and phone number, and start messaging your mobile contacts,” the statement said. “Just install the app and tap Get Started to reach your contacts faster, start group conversations, share photos and more.”

An update for Android phones has already been released, and the statement added that new independent “Messenger accounts” will be made available in the next few weeks. And iOS app is likely to emerge soon as well, but its timing has not yet been announced.

The announcement comes amid speculation about the state of messaging on mobile devices. Short message service (SMS) text messaging just turned 20 this week, but many analysts have already noted that the iconic mobile messaging service has lost ground to other mobile software alternatives such as WhatsApp, a popular mobile instant-messaging (IM) software that the Financial Times credited last year with having “done to SMS on mobile phones what Skype did to international calling on landlines.”

Facebook faced a fresh round of rumors this week about a possible acquisition of WhatsApp Inc., the creators of the popular IM program -- rumors the company squarely denied. Opening its messenger application would instead allow Facebook to stand up to its smaller competition in the startup space without having to resort to acqui-hiring.

A major selling point historically for a service like WhatsApp has been the fact that it is cross-platform and only required a phone number to set up an account. Owners of any phone using mobile operating systems including Android, BlackBerry OS, iOS, Series 40, Symbian, and Windows Phone could thus message each other without facing the frustrating compatibility issues that plague text messaging between popular smartphones like iPhones and Android models.

Of course, a native Facebook application exists for these mobile devices as well. But opening up a stand-alone Messenger service allows Facebook to hone in on a particular service, and potentially attract more users to the social network along the way.

Facebook shares rose around one-quarter of a percentage point during trading Tuesday morning, jumping as high as $27.40 per share in late-morning trading.